How do I do this?
Please help

Answer :
In the given quadrilateral ABCD ,
Angle BCA = Angle CAD ( alternate interior angle )
Now in triangle CAD ,
We have two angles so by using angle sum property we can find the required third one ,
Answer:
∠ ADC = 100°
Step-by-step explanation:
∠ CAD = ∠ BCA = 18° ( alternate angles )
The sum of the 3 angles in a triangle = 180° , then
∠ ADC = 180° - (62 + 18)° = 180° - 80° = 100°